Cable overheat simulation and cable outer sheath overheat produced gas collection device
The cable conductor heating simulates the cable overheating process and collects accurate gas production, thereby improving the accuracy of early warning of power cable fires, and solving the problem of insufficient fire warning accuracy in the prior art.
Patent Information
- Application Number
- CN202420988740.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-09
- Publication Date
- 2025-03-28
- Estimated Expiration
- 2034-05-09
AI Technical Summary
Power cable fires are difficult to effectively warn in the early stages, and the cross-sensitivity of the prior art limits the accuracy of fire warnings.
The outer sheath is heated through the high current of the cable conductor itself, which simulates and is completely consistent with the actual heat transfer process and collects accurate gas production to improve the accuracy of fire warning.
The accuracy of fire warning has been improved, and it can provide effective early warnings in the early stages of cable fires, reducing life safety threats to staff and firefighters.
Smart Images
Figure CN222689859U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of early warning of cable fires in cable tunnels for electric power workers, in particular to a gas generation and collection device for cable overheating simulation and cable outer sheath overheating. Background Art
[0002] Power cables are the carriers of power transmission and the arteries of the power system, which deeply affect the development of the national economy. Overload, short circuit, poor contact, arc, etc. may lead to fire accidents. Power cable fires are highly destructive. They not only damage power transmission equipment and reduce power supply reliability, but also produce toxic smoke, which poses a great threat to the lives of workers and firefighters.
[0003] Unlike other types of electrical fires, a large number of power cables are densely laid in closed trenches and tunnels, which makes cable fires concealed and flammable, so the alarm device is required to play a role in the early stages of cable fire development. Power cable fires are divided into multiple stages. In the early stages of the fire, it only manifests as abnormal temperature of the outer sheath without a lot of smoke. It then develops into smoldering with a lot of smoke, and finally an open flame appears until it is extinguished. The high temperature caused by the fault causes the chemical bonds of the polymer material that constitutes the outer sheath to begin to break, producing specific pyrolysis gases, which carry the temperature information of the cable. Studying the heat and gas production characteristics of the cable can improve the gas phase characteristics in the early stages of the fire.
[0004] XLPE also contains additives during the manufacturing process, such as voltage stabilizers, peroxide crosslinking agents, etc. The peroxide crosslinking agent DCP (Dicumyl Peroxide) decomposes under heat to produce crosslinking byproducts that affect the performance of XLPE. Therefore, the gas composition of early cable fires is very complex, and the cross-sensitivity of MOS gas sensors limits the accuracy of fire warnings.
[0005] The information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore may contain information that does not form the prior art that is known to a person of ordinary skill in the art. Utility Model Content
[0006] In view of the shortcomings or defects of the above-mentioned prior art, a cable overheating simulation and cable outer sheath overheating gas collection device is provided, which improves the accuracy of fire warning. By heating the outer sheath with a large current of the cable conductor itself, a heat transfer process that is completely consistent with the actual process can be simulated to obtain accurate gas production.
[0007] The purpose of the utility model is achieved through the following technical solutions.
[0008] A cable overheating simulation and cable outer sheath overheating gas collection device comprises:
[0009] The current booster includes an adjustable transformer, a switch, a voltmeter and an ammeter. The input end of the current booster is connected to the industrial frequency power supply, and the output end is connected to the experimental box.
[0010] The experimental box includes:
[0011] The box is an open hollow structure, and the box includes a plurality of screw holes, copper noses, copper busbars and air holes arranged on the top surface. The outgoing cable at the output end of the current booster is connected to the copper nose via a first fastener, and the experimental cable section for testing is connected to the copper busbar via a second fastener.
[0012] A box cover is detachably mounted on the box body, and the box cover includes a plurality of third fasteners for connecting the screw holes and a wire outlet hole.
[0013] a gas collection pipe connected to the gas hole,
[0014] An air pump is connected to the air sampling pipe and the air collecting bag.
[0015] In the cable overheating simulation and cable outer sheath overheating gas collection device, the open hollow structure is a hollow rectangular parallelepiped with a closed bottom.
[0016] In the cable overheating simulation and cable outer sheath overheating gas collection device, the sensor array is arranged in the box, the data line of the sensor array is led out through the outlet hole, and the data line is connected to the computer.
[0017] In the cable overheating simulation and cable outer sheath overheating gas collection device, the box is provided with a temperature gauge and a pressure gauge.
[0018] In the gas production and collection device for simulating cable overheating and cable outer sheath overheating, the gas collection pipe is connected to the air hole via a three-way valve.
[0019] In the cable overheating simulation and cable outer sheath overheating gas collection device, rectangular through holes for passing the wiring copper busbars are opened in the center of both sides of the box.
[0020] In the cable overheating simulation and cable outer sheath overheating gas collection device, the experimental cable section is fixed in the experimental box via a second fastener.
[0021] In the cable overheating simulation and cable outer sheath overheating gas collection device, two copper noses are arranged on both sides of the wiring copper bus and extend outwards respectively.
[0022] In the cable overheating simulation and cable outer sheath overheating gas collection device, a sealing ring is provided between the box body and the box cover.
[0023] Compared with the prior art, the beneficial effects brought by the utility model are:
[0024] The utility model improves the accuracy of fire warning, and is different from the external heating devices used in other cable outer skin overheating conditions. The outer sheath is heated by the large current of the cable conductor itself, and can simulate the heat transfer process that is completely consistent with the actual one to obtain accurate gas production.
[0025] The above description is only an overview of the technical solution of the utility model. In order to make the technical means of the utility model clearer and to achieve the extent that those skilled in the art can implement it according to the contents of the specification, and in order to make the above and other purposes, features and advantages of the utility model more obvious and easy to understand, the specific implementation methods of the utility model are illustrated below. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] By reading the detailed description of the preferred specific embodiments below, various other advantages and benefits of the utility model will become clear to those of ordinary skill in the art. The drawings in the specification are only used for the purpose of illustrating the preferred embodiments and are not considered to be limitations of the utility model. Obviously, the drawings described below are only some embodiments of the utility model. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings without creative work. Moreover, the same reference numerals are used to represent the same components throughout the drawings.
[0027] In the attached picture:
[0028] Figure 1 It is the electrical wiring diagram of the utility model;
[0029] Figure 2 It is a structural schematic diagram of an experimental box of an embodiment of the utility model;
[0030] Figure 3 It is a schematic diagram of the internal structure of an experimental box of an embodiment of the utility model.
[0031] The present invention will be further explained below in conjunction with the accompanying drawings and embodiments. DETAILED DESCRIPTION
[0032] The specific embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although the specific embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.
[0033] It should be noted that certain words are used in the specification and claims to refer to specific components. Those skilled in the art should understand that technicians may use different nouns to refer to the same component. This specification and claims do not use the difference in nouns as a way to distinguish components, but use the difference in the functions of the components as the criterion for distinction. As mentioned throughout the specification and claims, "including" or "comprising" is an open term, so it should be interpreted as "including but not limited to". The subsequent description of the specification is a preferred embodiment of the implementation of the utility model, but the description is based on the general principles of the specification and is not used to limit the scope of the utility model. The scope of protection of the utility model shall be determined by the definition of the attached claims.
[0034] To facilitate the understanding of the embodiments of the present utility model, several specific embodiments will be further explained below with reference to the accompanying drawings, and each of the accompanying drawings does not constitute a limitation on the embodiments of the present utility model.
[0035] For a better understanding, Figures 1 to 3 As shown, a cable overheating simulation and cable outer sheath overheating gas collection device includes:
[0036] The current booster includes an adjustable transformer 24, a switch 23, a built-in voltmeter 26, and a built-in ammeter 25. Its input end is connected to the industrial frequency power supply 21, and its output end is connected to the experimental box 22.
[0037] The experimental box 22 includes:
[0038] The box body 2 is an open hollow structure, and the box body 2 includes a plurality of screw holes 1, a copper nose 5, a copper busbar 8 and an air hole 6 arranged on the top surface. The output cable 3 of the current booster output end is connected to the copper nose 5 via a first fastener 4, and the experimental cable section 18 for testing is connected to the copper busbar 8 via a second fastener 19.
[0039] The box cover 12 is detachably covered with the box body 2, and the box cover 12 includes a plurality of third fasteners 20 for connecting the screw holes 1 and a wire outlet hole 13 provided therethrough.
[0040] The gas collection pipe 9 is connected to the gas hole 6.
[0041] An air pump is connected to the air sampling pipe 9 and the air collecting bag 11.
[0042] In a preferred embodiment of the cable overheating simulation and cable outer sheath overheating gas collection device, the open hollow structure is a hollow cuboid with a closed bottom.
[0043] In a preferred embodiment of the cable overheating simulation and cable outer sheath overheating gas collection device, a sensor array is arranged in the box 2, and a data line 17 of the sensor array is led out through the outlet hole 13, and the data line 17 is connected to a computer 16.
[0044] In a preferred embodiment of the cable overheating simulation and cable outer sheath overheating gas collection device, the box body 2 is provided with a temperature gauge 15 and a pressure gauge 14.
[0045] In a preferred embodiment of the gas production and collection device for simulating cable overheating and cable outer sheath overheating, the gas collection pipe 9 is connected to the gas hole 6 via a three-way valve 7 .
[0046] In a preferred embodiment of the cable overheating simulation and cable outer sheath overheating gas collection device, rectangular through holes are opened in the center of both sides of the box body 2 for passing the wiring copper busbar 8.
[0047] In a preferred embodiment of the cable overheating simulation and cable outer sheath overheating gas collection device, the wiring copper bus 8 includes a hollow rectangular structure.
[0048] In a preferred embodiment of the cable overheating simulation and cable outer sheath overheating gas collection device, the experimental cable segment 18 is fixed in the experimental box via a second fastener 19 .
[0049] In a preferred embodiment of the cable overheating simulation and cable outer sheath overheating gas collection device, two copper noses 5 are arranged on both sides of the wiring copper bus 8 and extend outwards respectively.
[0050] In a preferred embodiment of the cable overheating simulation and cable outer sheath overheating gas collection device, a sealing ring is provided between the box body 2 and the box cover 12.
[0051] In one embodiment, a hollow cuboid with a closed bottom has rectangular through holes in the center of both sides through which the wiring copper busbar 8 passes, and a circular vent hole 6 is opened in the center of the front side. The box cover 12 is fixed to the top of the box body 2 by a third fastener 20, and the gap between the box body 2 and the box cover 12 is sealed by a rectangular polytetrafluoroethylene sealing ring. The material is a synthetic stone that can withstand a high temperature of 300°C. A wire outlet hole 13 is provided in the central position of the box cover 12, and the data line 17 passes through the hole to transmit the signal of the sensor array from the inside to the outside. This device can arrange a sensor array to realize multi-sensor joint perception. The wiring copper busbar 8 is a rectangular copper busbar with a cross-sectional area of 1000mm2 and circular through holes at both ends. It is fixed to the box body 2 by high-temperature resistant non-volatile inorganic glue. The wiring copper busbar 8 connects the experimental cable segment 18 with the outlet cable 3 at the output end of the current booster. The air hole 6 is connected to the gas collection pipe 9 through the three-way valve 7, and further connected to the air pump. The air pump at one end is connected to the polytetrafluoroethylene gas collection bag 11 through the gas collection pipe 9 to collect the gas in the box in time, and the function of the air pump at the other end is to discharge the gas in the box. During the experiment, the cable surface is wiped clean with distilled water and dried, and a sample section is made. It is reliably connected to the device through the M8 bolt, and a stable current is passed to the cable section through the output end of the current booster until the cable surface temperature reaches a stable 90°C. A constant large current is applied for 10 minutes to rapidly heat the cable surface to the fault temperature, thereby simulating the sudden overheating fault of the cable. The designed fault temperature is 110°C to 180°C. Thus, the cable overheating fault at different temperatures can be simulated. After heating, the valve on the experimental box 22 is opened in time, and the gas is extracted by the air pump. Before collecting the gas, the gas collection bag 11 should be placed in a high-temperature oven consistent with the preset fault temperature for heating to avoid the condensation of gaseous compounds at high temperature into liquid.
[0052] A wire outlet hole 13 is provided at the central position of the box cover 12, through which the data line 17 transmits the sensor array signal from the inside to the outside to the computer 16. The box cover 12 is fixed to the top of the box body through the third fastener 20 and the screw hole 1. The wiring copper bus 8 is fixed to the box body 2 by a high-temperature resistant and non-volatile inorganic glue. The current booster outlet cable 3 and the experimental cable section 18 are connected to the copper nose 5 respectively and then connected to the wiring copper bus 8 through the first fastener 4 and the second fastener 19. The air hole 6 is connected to the gas collection pipe 9 through the three-way valve 7, and is further connected to the air pump 10 and connected to the gas collection bag 11. The pressure gauge 14 and the thermometer 15 are fixed to the box body 2 by a high-temperature resistant and non-volatile inorganic glue.
[0053] The basic principles of the present application are described above in conjunction with specific embodiments. However, it should be noted that the advantages, strengths, effects, etc. mentioned in the present application are only examples and not limitations, and it cannot be considered that these advantages, strengths, effects, etc. are required by each embodiment of the present application. In addition, the specific details disclosed above are only for the purpose of illustration and ease of understanding, not for limitation, and the above details do not limit the present application to being implemented by adopting the above specific details.
[0054] The above description has been given for the purpose of illustration and description. In addition, this description is not intended to limit the embodiments of the present application to the forms disclosed herein. Although multiple example aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, changes, additions and sub-combinations thereof.
Claims
1. A cable overheating simulation and cable outer sheath overheating gas collection device, characterized in that: These include, The current booster includes an adjustable transformer, a switch, a voltmeter and an ammeter. The input end of the current booster is connected to the industrial frequency power supply, and the output end is connected to the experimental box. The experimental box includes: The box is an open hollow structure, and the box includes a plurality of screw holes, copper noses, copper busbars and air holes arranged on the top surface. The outgoing cable at the output end of the current booster is connected to the copper nose via a first fastener, and the experimental cable section for testing is connected to the copper busbar via a second fastener. A box cover is detachably mounted on the box body, and the box cover includes a plurality of third fasteners for connecting the screw holes and a wire outlet hole. a gas collection pipe connected to the gas hole, An air pump is connected to the air sampling pipe and the air collecting bag.
2. The cable overheating simulation and cable outer sheath overheating gas collection device as claimed in claim 1 is characterized in that: The open hollow structure is a hollow cuboid with a closed bottom.
3. The cable overheating simulation and cable outer sheath overheating gas collection device as claimed in claim 1, characterized in that: The sensor array is arranged in the box body, and the data line of the sensor array is led out through the wire outlet hole, and the data line is connected to the computer.
4. The cable overheating simulation and cable outer sheath overheating gas collection device as claimed in claim 1, characterized in that: The box body is provided with a temperature gauge and a pressure gauge.
5. The cable overheating simulation and cable outer sheath overheating gas collection device as claimed in claim 1, characterized in that: The gas sampling pipe is connected to the gas hole via a three-way valve.
6. The cable overheating simulation and cable outer sheath overheating gas collection device as claimed in claim 1, characterized in that: Rectangular through holes are provided in the center of both sides of the box body for passing the wiring copper busbar.
7. The cable overheating simulation and cable outer sheath overheating gas collection device as claimed in claim 1, characterized in that: The test cable segment is fixed in the test box via a second fastener.
8. The cable overheating simulation and cable outer sheath overheating gas collection device as claimed in claim 1, characterized in that: Two copper noses are arranged on both sides of the wiring copper bar and extend outwards respectively.
9. The cable overheating simulation and cable outer sheath overheating gas collection device as claimed in claim 1, characterized in that: A sealing ring is arranged between the box body and the box cover.